We are requesting the replacement of basic animal care and use equipment dedicated to a comprehensive research program in molecular and cellular mechanisms of carcinogenesis, mutagenesis, and toxicology at The University of Texas M.D. Anderson Cancer Center Science Park. The research program staff that this equipment will support includes 55 doctoral level investigators and trainees. Current annual grant support for this program is more than $4,000,000, with NIH providing 80% of these funds. The University of Texas M.D. Anderson Cancer Center has supported this program with animal facility renovations and new animal care equipment purchases totaling $1,277,000 since January 1984. The requested animal care and use replacement equipment will allow the veterinary resources department of our institution to continue maintaining minimal PHS Animal Welfare Policies for the rapidly expanding animal care and use needs of a vital research program. The established veterinary service programs are committed to the necessity of well-defined, adventitious-pathogen-free rodent models to support the research objectives of this program. Formal genetic and health Quality Assurance Programs assure continuity in the quality of the animal models used in these very sophisticated investigations. The replacement equipment we are requesting is part of our scheduled replacement plan to assure our continued commitment to this level of quality veterinary services.